Hemstitching attachment for sewing machines



April 1s, 1939. G. l.. HINMAN 2,154,680.

IIIEMSTI'ICI-IING ATTACHMENT FOR SEWING MACHINES f Fild Oot. '7,y 1956 Patented Apr. 18, 1939 PATENT FFECE HEMSTITCHING ATTACHMENT FOR SEWING MACHINES George L. Hinman, New Haven, Conn., assigner to The Greist Manufacturing Company, New Haven, Conn., a corporation of Connecticut Application October 7, 1936, Serial No. 104,433

18 Claims.

This invention relates to hemstitching attachments for sewing machines, and more particularly to certain improvements in the Vdevice shown in the patent of myself and Clifford J. Word, No. 2,069,652, February 2, 1937.

As is well known, a hemstitching device comprises apparatus for piercing a hole in the material, making a stitch in this opening, moving the material laterally, and effecting -a stitch through the cloth at the side of the opening, effecting a lateral return of the material, and making another stitch within the opening, and then feeding the cloth forwardly in preparation for another hemstitching operation. The length or throw of this forward feeding step determines the length of the stitch, or the distance between two adjacent hemstitching operations, or two adjacent openings pierced in the cloth. Heretofore hemstitching attachments for sewing machines have been limited in that they have not been provided with means for adjusting the length of this stitch to perform coarse and line hemstitching work. In some cases the length of stitch has been adjustable to some extent, in order to coordinate the length of the feeding step with the distance between the piercer and the sewing machine needle, as these measurements must be the same for the proper operation of the device. Also, when the length of the feed step is shorter or longer, the opening in the goods formed by the piercer should be smaller or larger to do finer or coarser work, and, likewise, when the length of the feed step is changed, the distance between the point of the piercer and the sewing machine needle must be changed to correspond to the feed step. It is contemplated by the present invention, therefore, to provide a sewing machine attachment by means of which finer or coarser hemstitching operations may be effected, and by the employment of the principles of the invention, between the iinest and coarsest patterns produced, any number of intermediate patterns may be produced, as desired. Moreover, provision is made for the use of the piercer of the proper size corresponding to the length of the feed step to which the device is adjusted, and also for the proper variation of the distance between the piercer and the needle, so that this distance will be the same as the length of the feed step. This is necessary in order that the opening which has been previously formed by the piercer will `be advanced the proper amount by the feed step so that the sewing machine needle will correctly register with this opening.

One object of the present invention is the provision of a hemstitching attachment for sewing machines such that fine and coarse hemstitching operations may be performed thereby..

A still further object of the invention is the provision of a hemstitching attachment for sewing machines by which several degrees of hemstitching operations of ner and coarser patterns may be performed by adjustments of the device which may bemade with facility by any sewing machine operator.

Another object of the invention is the provision of a hemstitching attachment for sewing machines having provision for varying the length of the stitch between adjacent hemstitching operations, and also for varying the size o1" piercer employed with the various adjustments of the length of the feed stitch, together with provision for varying the distance between the point of any particular piercer and the sewing machine needle. so that the elements of the device will be properly coordinated to produce hemstitching operations of several degrees of neness or coarseness.

A still further object of the invention is the provision in an adjustable feed hemstitching attachment of means for visibly and unerringly indicating to the operator the particular adjustment at which the length of the feed step is set, so that the proper piercer for this particular adjustment may be selected and inserted in the attachment.

Still another object of the invention is the provision of interchangeable adapting members to provide for the securing of the attachment to sewing machines of various makes.

To these and other ends the invention consists in the novel features and combinations of parts to be hereinafter described and claimed.

In the accompanying drawing:

Fig. 1 is a side elevational view of a sewing machine attachment embodying my invention;

Fig. 2 is a sectional view on line 2-2 of Fig. 1;

Fig. 3 is an enlarged longitudinal sectional "View of a portion of the attachment;

Fig. 4 shows a piercer in plan and side views;

Fig. 5 is a view similar to Fig. 4, showing a piercer of different size and shape;

Fig. 6 is a partial sectional view taken on line 6--8 of Fig. 3; and

Fig. 'l is a plan View of the forward portion of the frame of the device showing a modified form of attaching member.

To illustrate a preferred embodiment of my invention, I have shown a hemstitching attachment comprising a frame including a horizontally arranged base plate I0 having upstanding side members II and I2. In these upstanding frame members a shaft I3 is rotatably mounted, which shaft carries a ratchet wheel I4 and cam wheels I5 and I6. These parts, and the other parts of the device not specifically described, will .be understood to be constructed similarly to the corresponding parts of the device shown in the Hinman and Word Patent No. 2,069,652, above referred to.

Pivoted upon the shaft I3 is an operating lever I1 carrying a pawl I8 which engages the teeth of the ratchet wheel I4 to turn the shaft I3 in a step-by-step movement as the lever I1 is reciprocated by the movement of the needle bar I9, with which the forked end 20 of this lever is connected. 'Ihe sewing machine needle carried by the needle bar I9 of the sewing machine is illustrated at 22.

Pivoted at 23 to the rear portion of the upstanding frame member II is a piercer-carrying arm 24, and connected to this arm at the forward end thereof is a piercer head 25 having an opening 26 through which may be inserted the shank or horizontal portion 21 of a piercer having a vertically extending pointed end 28. This shank is provided with a attened portion 29 against which impinges the end of a screw 36 threaded into the head 25 to hold the piercer in position in the head. Upon each side of the flat 29 may be provided a shoulder 3l, as shown more particularly in Fig. 4.

At the extreme forward end of the horizontal portion IU of the frame is provided a presser foot 32, and, as will be hereinafter explained, when the attachment is secured to a sewing machine, the usual presser foot will be removed and the attachment placed in substitution therefor, and connected with the presser bar, the foot 32 serving thereafter as the presser foot, which has been removed from the machine. Means are also provided at the forward end of the frame of the device for securing the attachment to the presser bar of the sewing machine. As various makes of machines differ in the construction of the presser bars, it is necessary, in order to make the device universally operable, that is, attachable to the presser bars of sewing machines of various makes, to provide attaching members or adapters of different construction. Provision is therefore made in the present device for attaching to the frame different forms of adapters, which are employed alternatively, depending upon the particular make of sewing machine with which the device is to be used. As shown, for example, in Figs. l and 2, an attaching member 33, which is substantially U-shaped in horizontal cross-section, is secured to the forward end of the upstanding frame member I2, this member being provided with an opening 34 to receive a securing screw (not shown) by which it may be attached to the presser bar. An adapter or securing member 35 of diiferent construction is shown in Fig. 7, which member is also secured to the forward part of the frame. This member is of U-shaped construction in vertical cross-section, having a lower leg 36 and an upper leg 31 provided with a horizontally disposed slot 35 designed to be secured to the presser bar. A brace member 39 of angle shape may be riveted to the member 35 and also riveted to the frame member II to hold the adapting member securely in place.

It will be understood that, as described in the Hinman and Word Patent No. 2,069,652, above referred to, means are provided in the attachment for feeding the cloth or material laterally during the hemstitching operation, as well as feeding it forwardly between successive hemstitching operations. This feeding is effected by means of a feed bar 46 disposed below the base member If! of the frame and secured thereto by means of a screw or rivet 4I, which is slidably engaged in a slot 42 in the member l0. This connection provides that the member 40' may have a pivotal movement with respect to the frame, so that the forward end of this member may move upwardly and downwardly while at the same time it may swing laterally to effect a lateral movement of the material, and also move slida-bly with respect to the frame member I in a backward and forward movement to effect a forward movement of the material, these movements all taking place as described in the Hinman and Word patent previously referred to. At the forward end of the feed bar 46, clothengaging teeth 43 are provided to engage the cloth and effect a forward feeding movement when the bar 40 is moved longitudinally with respect to the frame member ID.

Secured to the feed bar 40 is a small block 44 which projects upwardly through an elongated slot 45 in the member I0. Through this block is threaded a screw 46 having upon one end a Washer 41. Adjacent the other end this screw is provided with an enlarged shouldered portion 48 of circular shape, and outwardly of this portion the screw is of reduced size and provided with a slot 43 for the reception of a screw driver or other adjusting tool by which the screw may be rotated. A sheet metal cup-shaped member 5t is pressed upon the shouldered portion 48 of the screw, this cup-shaped member bearing numbers or indicia 5I to show the position or adjustment of the screw. Secured to the block 44 by means of the screw 52 is a sheet metal masking member 53, this member serving to cover the upper portion of the indicia-carrying member 55, and being provided with a opening 54 in its upper portion through which one of the indicia or indicating devices is visible, as shown more especially in Fig. 6. The mask 53 is, as stated, of sheet metal, and it is designed to bear lightly upon the indicia-carrying member 50 in order to frictionally hold the screw 44 in a given adjusted position, it being understood that the member 53 is somewhat resilient for this purpose.

A bell crank lever 55 is pivoted to the frame member II at 56, one end of this bell crank lever being adapted to be engaged by portions of the rotatable cam I6, and the other end of the bell crank lever being adapted to engage the washer 41 upon the screw 46. It will be apparent that when the longer end of the bell crank lever is given a throw to the right, as shown in Fig. 3, by the cam. I6, this lever, by acting upon the washer 4l', will move the block 44 and therefore the feed bar 4i! to the right, as shown in this figure. A return movement of the bar, when permitted by the bell crank lever, is effected by means of a spring 51, shown in Fig. 1. This return movement is limited, however, by engagement of the member 4I with the left-hand end of the slot 42, which engagement takes place prior to the engagement of the member 41 with the arm 55 of the bell crank lever when the latter is in its forward position, even when the member 41 is in its extreme left-hand position, as shown in Fig. 3. When the member 41 has been moved to the right by the adjusting screw 46, there will be,

therefore, a certain amount of lost motion ofv the bell crank lever 55 when it is actuated by the cam I6 before this member strikes the member 41.

It will be apparent that adjustment to the right or left, as shown in Fig. 3, of the washer 41 will determine the length of throw or amount of movement given to the feed bar, and as this movement effects the forward feeding of the cloth or material for the stitch between adjacent hemstitch patterns, the length of this stitch may be adjusted by turning the screw 46 so as to adjust the position of the washer 41 relatively to the longer endof the bell crank 55. The movement of this screw is limited in one direction by the enlarged shoulder portion 48 when it abuts the block 44, and is limited in the other direction by the washer 41 abutting the other side of the block 44. As illustrated, the extreme positions of the member 41 are obtained with less than a single turn of. the screw 46, whereby the indicia or indicating members arranged on the member 50 will never appear more than once in the opening 54 during its limited travel between the extreme positions permitted by the limiting stops, so that each indicating character will correctly indicate a corresponding position of the member 41 and consequently a corresponding throw of the feed bar 40 and length of stitch between successive hemstitching operations.

As previously stated, when the length of stitch is changed, a different size piercer should be used, and also the distance of the piercer point from the sewing machine needle should be changed to correspond with the length of stitch. As illustrated, the indicia 5l are numbers 1 to 4, and four different lengths of stitch are thus arranged for. It will be understood, however, that any convenient number may be employed as desired. As a different piercer is employed with each adjustment of the screw 46, four different piercers are provided with the four ad justments of the screw, and two of these piercers are shown in Figs. 4 and 5 of the drawing. It will be observed that, as shown in Figs. 3 and 6, when the indicia 1 is visible through the opening 54, the washer 41 is moved to the extreme left position against the bell crank lever 55 and thus the longest feed stroke or stitch length is effected. The piercer shown in Fig. 4, which bears the numeral 1, is designed to be used with this adjustment of the screw 46,and the piercer point 28 will be the largest in size or of a size to make the largest opening in the cloth. Also it will be noted that the shank 21 of this piercer is substantially straight. When the screw 46 has been turned to bring the second indicating character below the opening 54, the piercer marked No. 2 will be used, as shown in Fig. 5. The point of this piercer is slightly smaller than the point 28 of the piercer shown in Fig. 4, so that this piercer will effect a slightly smaller opening in the material. Also, it will be noted that the shank 6| of this piercer is slightly offset, as shown at 62, the offset being toward the needle 22, so that the piercer point will be slightly closer to the needle than is the case when the No. 1 piercer is employed. Similarly, when the third and fourth positions of the screw 46 are employed, the numerals 3 and 4 will appear in the opening 54, and different piercers marked 3 and 4 (not shown) will be employed. The points of these piercers will be progressively smaller than the No. 2 piercer, and the offsets will be progressively greater, so that these pierciers will make progressively smaller holes in the cloth, and likewise their points will be closer to the needle 22 to correspond with the reduction in the length of the stitch between successive hemstitching operations.

It will be apparent that by the present device I provide for several degrees of fine and coarse hemstitching, the invention obviously not being limited to the four degrees shown and described, but the number and range of adjustments of the screw 46 may be carried as far as desired. Likewise, with each adjustment of the length Aof stroke of the feed'bar, provision is made for using a piercer of the pro-per size and one the point of which will be disposed at the proper distance from the sewing machine needle. Also, the adjustment is made very easy by reason of the fact that a proper indicating member or number appears in the opening 54 at the various adjustments of the screw 46, which will indicate the proper piercer to be employed. Owing to the fact that the screw 46 is limited to less than one revolution, none of these numerals will appear within the opening 54 except in the proper position of the screw, so that there will be no opportunity for error in this respect. Preferably these numerals are arranged upon the rear side or inside of the member 50, so that they will not be seen at all except through the opening 54.

While I have shown and described a. preferred embodiment of my invention, it will be understood that it is not to be limited to all of the details shown, but is capable of modification and variation within the spirit of the invention and within the scope of the appended claims.

What I claim is:

1. In a hemstitching attachment for sewing machines, a frame, means carried by the frame to effect a hemstitching operation on material fed thereto, said means including a pointed piercer, means to feed the material progressively to said hemstitching means, rotatably adjustable means to vary the length of stitch between adjacent hemstitching operations, and means for correspondingly varying the position of the piercer point with respect to the frame.

2. In a hemstitching attachment for sewing machines, a frame, means carried by the frame for performing a hemstitching operation on material` fed thereto, means to feed material progressively to said hemstitching means, means to adjust said feeding means to Vary the length of stitch between adjacent hemstitching operations, said adjusting means carrying indicia to indi` cate the length of stitch 'effected by the respective adjustments and a mask concealing certain of said indicia.

3. In a hemstitching attachment for sewing machines, a frame, means carried by the frame for performing a hemstitching operation on material fed thereto, means to feed material progressively to said hemstitching means, means to adjust said feeding rneans to vary the length of stitch between adjacent hemstitching operations, and said adjusting means carrying indicia to indicate the length of stitch effected by therespective adjustments, and means rendering the proper one only of said indicia visible to the operator at a given adjustment of the stitch length.

4. In a hemstitohing attachment for sewing machines, a frame, means carried by the frame for performing a hemstitching operation on material fed thereto, means to feed material progressively to said hemstitching means, means rotatable to adjust said feeding means to vary the length of stitch between adjacent hemstitching operations, and indicating means movable with said adjusting means to indicate the stitch length effected by the respective adjustments.

5. In a hemstitching attachment for sewing machines, a frame, means carried by the frame for performing a hemstitching operation on material fed thereto, means to feed material progressively to said hemstitching means, means to adjust said feeding means to vary the length of stitch between adjacent hemstitching operations, and said adjusting means carrying indicia to indicate the length of stitch effected by the respective adjustments, means rendering the proper one of said indicia visible to the operator at a given adjustment of the stitch length, and said hemstitching means including a piercer-carrying member and a piercer carried thereby, said piercer having a shank and a point offset relatively to the shank, and. said piercer carrying indicia corresponding to certain of said indicia on the adjusting means.

6. A hemstitching attachment for sewing machines comprising a frame, means carried by the frame for performing a hemstitching operation on material fed thereto, means tofeed material progressively to said hemstitching means, means to adjust said feeding means to vary the length of stitch between adjacent hemstitching operations, said adjusting means including a rotatable member, said member carrying indicating characters to indicate the length of stitch of a given adjustment, means normally concealing said characters from view, and said means being provided with an opening to render a predete-rmined character visible at a given adjustment of said stitch length.

7. A hemstitching attachment for sewing machines comprising a frame, means carried by the frame for performing a hemstitching operation on material fed thereto, means to feed material progressively to said hernstitching means, means to adjust said feeding means to vary the length of stitch between adjacent hemstitching operations, said adjusting means including a rotatable member, said member carrying indicating characters to indicate the length of stitch of a given adjustment, means normally concealing said characters from view, said means being provided with an opening to render a. predetermined character visible at a given adjustment of said stitch length, and said rotatable member being limited to not more than one rotation.

8. A hemstitching attachment including a frame, a feed bar movably attached to the frame to feed the material past the attachment, a lug secured to said feed bar and extending upwardly therefrom, actuating means for said feed bar, means carried by said lug and adapted to be engaged by said actuating means to effect a feeding movement of the feed bar, and said means being adjustable relatively te said lug in the direction cf movement of said actuating means to vary the stroke of the feed bar.

9. A hemstitching attachment including a frame, a feed bar movably attached to the frame to feed the material past the attachment in a step-by-step movement, actuating means to effect a feeding stroke of said feed bar, a lug secured to said feed bar and extending upwardly therefrom, an abutment carried by said lug and adapted to be engaged by said actuating means to effect said feeding stroke, and means for adjusting said abutment relatively to said lug in the direction of movement of said actuating means to Vary the length of the feeding stroke.

l0. A hemstitching attachment including a frame, a feed bar movably attached to the frame to feed the material past the attachment in a step-by-step movement, actuating means to effect a feeding stroke of said feed bar, a lug secured to said feed bar and extending upwardly therefro-m, an abutment carried by said lug and adapted to be engaged by said actuating means to effect said feeding stroke, and means for adjusting said abutment relatively to said lug in the direction of movement of said actuating means to vary the length of the feeding stroke, said means comprising a member threadedly engaged with said lug and carrying said abutment at one end thereof.

il. A hemstitching attachment including a frame, a feed bar movably attached to the frame to feed the material past the attachment in a step-by-step movement, actuating means to effect a feeding stroke of said feed bar, a lug secured to said feed bar and extending upwardly therefrom. an abutment carried by said lug and adapted to be engaged by said actuating means to effect said feeding stroke, and means for adjusting said abutment relatively to said lug in the direction of movement of said actuating means to vary the length of the feeding stroke, said means comprising a member threadedly engaged with said lug and carrying said abutment at one end thereof, and said member carrying indicia thereon to indicate the length of the feeding stroke.

l2. A hemstitching attachment including a frame, means carried by the frame for perform- I ing the hemstitching operation on material fed thereto, including a piercer, said piercer having a shank and a point disposed at an angle to said shank, and said point being offset with respect to the axis of the shank.

13. A hemstitching attachment for sewing machines comprising mechanism for effecting hemstitching operatic-ns upon a piece of material, said mechanism including means to progressively feed the material past the needle of the sewing machine to space said hemstitching operations, said feeding means being adjustable to vary the spacing between adjacent hemstitching operations, and said hemstitching means including a piercer having a shank and a point offset with respect to the axis of the shank, the amount of said offset corresponding to the adjustment of said feeding means.

14. A hemstitching attachment for sewing machines comprising means to feed the material to be operated upon past the attachment in a step by step movement, said feeding means being adjustable to vary the spacing between adjacent hemstitching operations, and said attachment including a piercer having a shank and a point cifset with relation to the shank.

15. A hemstitching attachment for sewing machines comprising a frame, means movably mounted on the frame to progressively feed the cloth past said attachment, means carried by the frame to effect hemstitching operations between successive feeding movements, said feeding means being adjustable to vary the length of the feeding movement to vary the spacing between adjacent hemstitching operations, said attachment including a piercer having a shank and a piercing point offset with relation to the shank to effect a predetermined spacing between the piercer point and the needle of the sewing machine.

Tio

16. In a hemstitching attachment for sewing machines, a frame, means carried by the frame to eiect hemstitching operations on material fed thereto, said means including a pointed piercer, means to feed the material progressively to said hemstitching means, said feeding means being adjustable to vary the length of stitch between adjacent hemstitching operations, and said piercer being shaped to space the point thereof at a. predetermined distance from the sewing machine needle corresponding to the adjustment of said feeding means.

17. In a hemstitching attachment for sewing machines, a frame, means carried by the frame to effect a hemstitching operation on material fed thereto, means to feed material progressive- 1y to said hemstitching means, said feeding means being adjustable to vary the length of the stitch between adjacent hemstitching operations, said hemstitching means including a piercer-carrying member, and a piercer secured to said member,

said piercer having a pointed end the size of which bears a definite relation to the adjusted length of the stitch between adjacent hemstitching operations.

18. In a hemstitching attachment for sewing machines, a frame, means carried by the frame to effect a hemstitching operation on material fed thereto, means to feed material progressively to said hemstitching means, said feeding means being adjustable to Vary the length of the stitch between adjacent hemstitching operations, said hemstitchng means including a piercer-carrying member, and a piercer secured to said member, said piercer having a pointed end oset with relation to the shank to space said point a predetermined distance from the needle of the sewing machine, the amount of said oiset corresponding to the adjusted length of the stitch between hemstitching operations.

GEORGE L. HINMAN. 

